1. Field of the Invention
The present invention relates to a substrate including thin film transistors (TFTs), and an organic light emitting display apparatus including the substrate, and more particularly, to an active-matrix (AM) bottom emission type organic light emitting display apparatus.
2. Description of the Related Art
Recently, display apparatuses have been replaced with portable, thin flat panel display apparatuses. Among the flat panel display apparatuses, electroluminescent display apparatuses are self-emissive display apparatuses that display an image by using light generated by recombination of electrons and holes in an emission layer (EML), and that have a wide viewing angle, an excellent contrast ratio, and a high response speed, and thus are regarded as next-generation display apparatuses.
In general, organic light emitting display apparatuses may be classified into a passive-matrix (PM) type organic light-emitting display apparatus and an active-matrix (AM) type organic light-emitting display apparatus according to the method of driving an organic light emitting diode (OLED).
Also, the organic light emitting display apparatuses may be classified into a top-emission type organic light emitting display apparatus in which an image is realized toward an encapsulation substrate, and a bottom-emission type organic light-emitting display apparatus in which an image is realized away from the encapsulation substrate.
In the AM type organic light emitting display apparatus, at least two thin film transistors (TFTs) and at least one capacitor are arranged in one pixel. However, in the bottom-emission type organic light emitting display apparatus, the TFTs and the capacitor should not be disposed in a direction in which light is emitted on a light emission path, and thus the bottom-emission type organic light emitting display apparatus may have a limit as to an aperture ratio.